Pyroquickness Hat

Pyroquickness Hat is a very rare Hat that burns the wearer when casting a Fire spell, but also grants them an extra Bonus Action.

Merely holding the circlet makes your skin flush, filling you with determination and righteous fury.

Properties

The wearer of this item gains:

Fiery Return: When you deal ⁠Fire damage with a levelled spell, you  Burn yourself and gain an additional  Bonus Action this round.

 See Invisibility or  Faerie Fire can be used to see the invisible chest.
The  Helldusk Armour or  Wet condition can negate the self-burning effect on the wearer while still allowing them to receive the extra bonus action.

Regarding Fiery Return:

The conditions for activating Fiery Return are to deal fire damage with a non-cantrip spell or a melee spell attack roll.
- Attacks with a  Flame Blade conjured by the druid spell count as melee spell attacks, so they trigger Fiery Return. However, this is not true of a Flame Blade summoned by a mephistopheles tiefling's racial feature or a permanent Flame Blade acquired through the exploit described here.
- The  Daredevil Gloves can turn ranged spell attacks into melee spell attacks, so cantrips like  Fire Bolt can trigger Fiery Return when paired with the gloves.

Regarding Fiery Return:

If Fiery Return is triggered with a  Bonus Action (for example, with  Metamagic: Quickened Spell), the extra bonus action granted by this passive is wasted and consumed immediately.
 Hellcrawler, a class action granted by the  Helldusk Boots, triggers Fiery Return, essentially negating the bonus action cost.
 Searing Smite does not trigger Fiery Return.